How the Virtual Border Fence Works

The virtual border fence will be used to compliment some physical fencing already in place, and in some cases, there will be no visible fencing at all.
Photo courtesy stock.xpert

In a test area near Sasabe, Arizona, a 28-mile section of the virtual border fence is set to go live. Developed by Boeing as part of a $70 million contract, the test fence, dubbed Project 28, will use a combination of physical fencing and "invisible technology" [Source: NPR].

This test section of the virtual fence is part of the larger Secure Border Initiative, designed to stop smugglers and illegal migrants along the United States' borders with Mexico and Canada. The Project 28 location was chosen in part because it's an area that has been riddled with smugglers.


To build its fence, Boeing has used fencing, vehicle barriers, radar, satellite phones, computer-equipped border control vehicles, underground sensors, 98-foot tall towers with high-powered cameras (including infrared cameras) and unmanned aerial vehicles. The tower-mounted cameras are extremely powerful; they have a range of more than 10 miles and the ability to determine if someone is armed from miles away.

Some parts of Project 28 have few or no visible measures in place, generally because it would be impractical to build a physical fence there, either because of cost or harsh terrain. However, the sections without visible fencing are reported to still be monitored by cameras, radar, underground sensors, Border Patrol agents and other technologies.

Next, we'll s­ee how these various technologies work together to make a virtual border fence.


Virtual Border Fence Technology

Border Patrol agents work with a helicopter flying overhead to police the border.
Public domain image

So how can a "virtual" fence work? Whenever a suspicious person or potentially illegal activity is detected near one of the fence's components, that information transmits to the Border Patrol offices in Tucson and Sells, Arizona. Agents in those offices notify agents in the field. The exact coordinates appear on laptops that the agents have in their vehicles. Images, coordinates, radar scans and all other information are combined to make a Common Operating Picture.

Using aerial photos of the border area, Boeing attempted to figure out how long it takes someone illegally crossing the border to "blend into" nearby urban areas [Source: NPR]. Physical fencing has been built at those spots, rather than along the exact border. The area leading up to that demarcation will be closely monitored by the virtual fence.


The virtual fence system is supposed to be able to operate at all times of day and in all types of weather. The hope is that it will significantly improve border security and provide a compliment to the physical fencing and Border Patrol personnel already in place. In the coming months and years, more security measures are supposed to go online. Boeing has presented a plan for 1,800 towers like those used in Project 28, to be placed along the United States' borders with Mexico and Canada. The U.S. government plans to hire 6,000 new Border Patrol agents by 2008. Until those new agents are in place, 6,000 National Guard members are at the border, helping with patrols, installing security systems and training Border Patrol agents.

In all, the virtual border fence seems like a very impressive project, a way of using cutting-edge technology to better monitor America's massive borders. The intended advantage of the virtual border fence is that it offers more flexibility than a strictly physical fence. But the project has also received a significant amount of criticism. In the next section, we'll look at some of the controversies surrounding the virtual border fence.


Criticisms of the Virtual Border Fence

Conservationists are concerned that the habitat of the endangered Texas Ocelot may be disrupted by the building of a border fence.
Public domain image

Many people, including residents of border towns, environmental activists, privacy advocates and government watchdog groups, have raised concerns about the fence's impact on the environment, economic activity, tourism and privacy.

Some critics question the technology behind the virtual fence. For example, cows have set it off. A concerned rancher also told the Associated Press that a government official had indicated that the tower's warning horn could go off automatically if anything -- human or animal -- gets too close [Source: St. Louis Tribune].


It's also unclear how much the full virtual fence will cost. Companies competing for border security contracts have said it's a $2 billion contract over six years. But the costs of past border fences, such as the one in development since 1994 along parts of the California-Mexico border, have skyrocketed beyond initial estimates. The cost of the new, complete virtual fence could be as much as $30 billion.

Privacy remains a concern for residents of towns near the virtual fence. Many residents of these communities enjoy their secluded living conditions. Given their extremely long range and proximity to some towns, the tower-mounted cameras could be used to look into private homes and businesses. The government says they won't be used for that purpose, but privacy advocates and local residents are concerned. Besides the cameras, underground sensors, helicopters and Border Patrol vehicles could leave border town residents feeling like they're under constant surveillance.

The territory along the Arizona-Mexico border contains important migratory routes for animals and several national parks. The virtual fence's towers, vehicles and helicopters could disturb animals in the area. Questions have been raised about whether the use of radar will adversely affect bats and honeybees. The physical portions of the fence are set to pass through areas frequented by rare animals such as the ocelot.

But illegal immigration exacts its own toll on the environment. Large amounts of litter and waste are strewn along migrant routes. Truckers and off-road vehicles carve illegal roads through canyons and hillsides, disrupting the natural habitats of local animals.­

Beyond privacy and environmental concerns, there's the question of whether the way of life for people living along the U.S.-Mexico border will change. We'll look at this in the next section.


Life along the U.S.-Mexico Border

Physical fencing is still considered essential in areas like this one, where Nogales, Arizona (left) is separated from Nogales, Mexico.
Public domain image

So how might a border fence affect the people living on either side of it? Parts of the physical border fence are planned for territory that is Native American tribal land. Increased traffic, Border Patrol agents and National Guardsmen has already been a source of complaint for some ranchers. The 98-foot towers in place on the periphery of towns represent a potential eyesore, and their warning sirens could drive away tourists from some of the nearby ranches that also serve as secluded vacation spots.

The Rio Grande Valley provides an important case study for this debate. In the valley, the cities of McAllen, Texas, and Reynoso, Mexico, are separated by the Rio Grande. However, many residents of the towns simply consider McAllen and Reynoso to be one town with a river flowing down the middle [Source: NPR]. The proposed fence would separate these cities and has created an outcry among local residents. Some people work in one city and live in another, crossing the border daily. Families on one side of the border have relatives on the other. The area also depends significantly on its agricultural economy and on tourism. Over the last 30 years, $100 million has been spent restoring natural habitats in the area. Even a virtual fence with towers, vehicles and radar stations could split this cross-border community in two and upset the work that has been done to repair the river's ecosystem.


However, border fence advocates point to the human cost of illegal immigration. Since 1994, more than 3,000 people have died trying to cross the border into southern Arizona. A better secured and more vigilantly-monitored border may help to save the lives of migrants lost in this unforgiving landscape.

Because of the many concerns that have been raised, some towns have held meetings with Boeing officials and representatives of the Border Patrol and the Department of Homeland Security. Congressional representatives have introduced legislation designed to respond to the concerns of their constituents, while other groups have filed lawsuits in court.

We've discussed some of the concerns about the impact of the physical and virtual border fences and the costs involved, but will it work? Read on to find out.


Effectiveness of the Virtual Border Fence

Towers similar to this one form part of the virtual and physical fences, using sophisticated cameras and other technology to monitor the border.
James Tourtellotte/U.S. Customs & Border Protection

Tracking the effectiveness of border security is a difficult task. Does the number of arrests of illegal immigrants and drug traffickers indicate success? If there are fewer arrests, does that mean people are being deterred by the fence or simply finding another way around? If there are more arrests, does that mean more people are slipping into the country unnoticed or that enforcement has improved? These are questions that commentators, politicians and law enforcement officials continue to ponder.

What's beyond dispute is that the virtual border fence uses top-of-the-line technology. Some aspects of the virtual fence have been used before along the California-Mexico border and in Iraq and Afghanistan, but never before have so many diverse technologies come together to police one border. Will that give law enforcement the upper hand, or will a network of up to 1,800 towers, each with its own set of cameras, radars and other devices, overwhelm the understaffed Border Patrol? Again, answering these questions will take time. But critics point to past efforts at boosting border security in which billions of dollars have been doled out, frequently with disappointing results. The fence along parts of the California-Mexico border is still unfinished after 13 years of construction and is far over budget. In other cases, contracts were awarded only to have cameras not installed, numerous false alarms and an increase rather than a decrease in illegal traffic. On April 25, 2007, the Border Patrol's sole Predator 2 drone, a $6.5 million unmanned aerial vehicle frequently used by the U.S. military in Iraq and Afghanistan, crashed in Arizona after only seven months of use.


Border security is an issue that many Americans care strongly about. Proponents of virtual and physical fencing point not only to the need to decrease illegal migrant traffic but also to concerns about drug smuggling and terrorism. On December 14, 1999, Ahmed Ressam was stopped and arrested near a Canadian border crossing. He was on his way to Los Angeles to attempt to blow up Los Angeles International Airport as part of the "Millennium Plot." Border security advocates cite this foiled terrorist operation as evidence that improving border security goes beyond stemming illegal immigration.

For more information about the virtual border fence and other related topics, check out the links on the next page.


Lots More Information

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  • "The Millenium Plot."
  • "'Virtual fence' unwelcome eyes in the sky." Associated Press. Northwest Herald. June 11, 2007.
  • Broache, Anne. "Administration touts 'virtual border fence plans." CNet News. June 1, 2006.
  • Davis, Tony. "Grijalva seeks environmental alternatives to border fence." Arizona Daily Star. June 11, 2007.
  • Goodwyn, Wade. "Plans for 20-Foot Border Fence Rile Texas Residents." NPR. June 15, 2007.
  • Hsu, Spencer S. and White, Griff. "Plenty of Holes Seen In a 'Virtual Fence.'" Washington Post. Sept. 21, 2006.
  • Inskeep, Steve and Robbins, Ted. "U.S. Tests 'Virtual' Border Fence in Arizona." NPR. June 18, 2007.
  • McEver, Melissa. "Environmental groups petition feds to consider border fence's impact on wildlife." The Monitor. June 13, 2007.
  • Rothstein, Arthur H. "Virtual fence along Mexican border has turned ranchers' solitude into 'war zone.'" Associated Press. The Salt Lake Tribune. June 4, 2007.